1. Field of the Invention
The present invention relates to a mobile body such as a robot, and more particularly, to an apparatus and method for estimating the location of the mobile body and generating a map of the mobile body environment using an upper image of the mobile body environment, and a computer readable recording medium storing a computer program for controlling the apparatus.
2. Description of Related Art
In conventional methods of generating a map of a robot environment, a very precise map can be obtained using scan matching, but a very high-priced sensor such as a laser range finder is required. One such conventional method is disclosed in the paper entitled “Robust Monte Carlo Localization for Mobile Robots,” S. Thrun, D. Fox, W. Burgard, and F. Dellaert, Artificial Intelligence, Vol. 128, No. 1-2, 2000, pp. 99-141. In the above conventional method, a map is generated using ceiling images as well as a laser range finder. However, since the ceiling images should be stored altogether, a large computational amount is required and recognizing a location of robot and generating a map of a robot environment cannot be simultaneously performed. Another conventional method is disclosed in the paper entitled “Simultaneous Localization and Map Building Using Natural Features and Absolute Information,” Jose Guivant, Favio Masson, and Eduardo Nebot, Robotics and Autonomous Systems, 984, 2002, pp. 1-12. This conventional method is suggested to be mainly used outdoors. In the method, generating a map of a robot environment and recognizing a location of the robot can be simultaneously performed. However, even in the method, a high-priced laser range finder should be used. Another conventional method is disclosed in the paper entitled “Visual Correction of Orientation Error for a Mobile Robot,” S. Lang, F. Yili, and S. K. Tso, Proc. of International Conf. on Intelligent Robots and Systems, 1999, pp. 1328-1333, and in U.S. Pat. No. 5,793,934 entitled “Method for the Orientation, Route Planning and Control of an Autonomous Mobile Unit”. However, even in this case, recognizing a location of a robot and generating a map of a robot environment cannot be simultaneously performed.
Another conventional method of recognizing a location of a robot and generating a map of a robot environment are also disclosed in the paper entitled “Real-Time 3D SLAM with Wide-Angle Vision”, Andrew J. Davison, Yolanda Gonzalez Cid, and Nobuyuki Kita, Proc. IFAC Symposium on Intelligent Autonomous Vehicles, 2004. All the conventional methods are affected by illumination. Another conventional method is disclosed in the paper entitled “Mobile Robot Localization and Mapping with Uncertainty Using Scale-Invariant Visual Landmarks”, Stephen Se, David Lowe, and Jim Little, International Journal of Robotics Research, Volume 21, Number 8, August 2002, pp. 735-758. In this conventional method, two cameras should be used and the method is affected by illumination variation so that a location of a robot and a map of a robot environment cannot be precisely respectively recognized and generated.